Hey, Note: UNO R3 supports 8-bit PWM resolution, not 10. Higher resolution means the PWM output can be more finely tuned, resulting in a smoother signal. This is particularly important in applications like motor control, LED dimming, and audio signal generation. 8-bit resolution means there are 256 possible Duty cycle values (from 0 to 255). That's why the analogWrite(PWM pin, PWM value) takes values bw 0 and 255. In this case, increasing the Duty cycle step by step corresponds to a change of approximately 0.4% (1/256) of the full-scale value. Whereas the 16-bit resolution means there are 65,536 possible Duty cycle values (from 0 to 65,535).Each step in the Duty cycle corresponds to a change of approximately 0.0015% (1/65,536) of the full-scale value. As much as the resolution is important, so does the frequency of the PWM signal. The increase in PWM resolution decreases the maximum PWM frequency possible for the same clock frequency. if UNO and ESP32 have the same clock frequency i.e., 16 MHZ. The maximum possible PWM frequency(16-bit) for ESP32 will only be 244 Hz. Whereas for UNO(8-bit), it is 62.5 KHz. For example, 16 MHz / 256 and 16 MHz / 65,536. EDIT: Hey everyone! Let’s clear up the confusion regarding PWM resolution and the difference between dividing by 2^n versus 2^n - 1 The Hardware Timer Perspective In fast PWM mode, the timer counts from 0 up to a “TOP” value and then overflows back to 0. For 8-bit PWM, TOP = 255. This gives you a counter range of 0–255 = 256 distinct counts. For 2-bit PWM, TOP = 3. This gives you a counter range of 0–3 = 4 distinct counts. Thus, in terms of raw timer ticks, there are 2^n counts per cycle. The Duty Cycle Perspective When calculating Duty cycle, we typically use: Duty Cycle (%)= (Compare Register Value/TOP) ×100. For 8-bit PWM, you divide by 255 (TOP = 255), so the highest compare value 255 yields 100 % Duty cycle. For 2-bit PWM, you divide by 3 (TOP = 3), so a compare value of 3 yields 100 % Duty cycle. If you were to divide by 2^n directly (e.g., 256 for 8-bit), the maximum compare value (255) would give (255/256)x 100 =~ 99.6% which technically matches clock ticks but doesn’t align with the usual definition of 100 % on hardware PWM outputs. Why It Matters 0 % Duty cycle: Compare Register = 0. 100 % Duty cycle: Compare Register = TOP (which is 2^n - 1). Users generally expect that the maximum compare setting translates to the output being fully ON (i.e., 100 %). Summary The timer truly counts 2^n steps (from 0 to 2^n−1). However, to get a Duty cycle percentage from 0 % to 100 %, you divide the compare value by 2^n - 1. That’s why for 8-bit PWM, you’ll see many references to dividing by 255, not 256.

Servo jitter in Arduino projects is usually caused by power instability, electrical noise, long signal wires, or software timing conflicts. To reduce it, use a separate and stable power supply for the servo (not the Arduino 5V pin), and connect all grounds together. Add a 100 µF–470 µF electrolytic capacitor near the servo’s power pins and a small 0.1 µF ceramic capacitor for noise filtering. A 220–470 Ω resistor in series with the signal line can also help. On the software side, avoid writing the same servo position repeatedly, filter noisy input signals, and use small delays or smoothing functions to prevent rapid position changes. These steps usually eliminate most servo jitter problems.

Hello paul, In Arduino, the analogWrite function is used to generate a PWM signal on a specified pin. The value parameters ranging from (0-255) you provide determines the Duty cycle of the PWM signal. Value of 0: This means the pin is always off (0% Duty cycle). Value of 255: This means the pin is always on (100% Duty cycle). Values between 0 and 255: These values correspond to Duty cycles between 0% and 100%. For example, a value of 127 would create a 50% Duty cycle. This allows for precise control of analog devices, such as LEDs or motors, using digital signals.

@ankunegi The answer is on point but I think there's a mistake in your calculation. To calculate the Duty cycle, we have to divide it by 255(the maximum value) and not 256(The total no. of steps). For example: A 2-bit PWM signal has 4 possible steps: 0,1,2 and 3 corresponding to 0%, 33.33%, 66.67% and 100% Duty cycle. You get this by dividing by 3, not 4. If you divide it by 4, you will get 25%. Which means 0%, 25%, 50% and 75%. See, you are not getting 100% Duty cycle in this case.

To the point answer by Techtalks. Just WAnt to add one important point here: The PWM pins on UNO have an 8-bit resolution. This gives us 256 discrete Duty cycles, since 2^8 = 256. Example: 2 bit means 4 possible Duty cycles. For PWM, they would be: 0, 33.33%, 66.66%, and 100%. Similarly, 4-bit means 16 Duty cycles, and 8-bit means 256 cycles. Now why does the PWM range from 0 to 255 and not 256? Because when you count 0, the total values from 0 to 255 are 256.

I think it’s less about “Arduino vs. ESP32” and more about picking the right tool for the job. Arduino is still fantastic for: Beginners learning electronics and coding. Quick prototypes that don’t need Wi-Fi or Heavy processing power. Reliable, simple projects like controlling LEDs or reading basic sensors. For IoT or real-time applications, ESP32 or Raspberry Pi Pico W is a better choice. But I’d say Arduino’s relevance comes from its accessibility. Many professionals started their careers with Arduino, and that familiarity keeps it in the game.

Yes, you can hook these pins to the PWM pin on Arduino. The Enable pin on the L298N acts as a gatekeeper for the power supplied to the motor. When the pin is set HIGH, the motor is enabled and can run. When set LOW, the motor is disabled and stops. By connecting the Enable pin to a PWM-capable pin on the Arduino and sending a PWM signal, you can control the effective voltage supplied to the motor. This changes the speed of the motor: A higher Duty cycle (e.g., 100%) means the Enable pin is HIGH most of the time, allowing full power to the motor and thus full speed.A lower Duty cycle (e.g., 50%) means the Enable pin is HIGH only half the time, reducing the average power supplied to the motor and thus reducing the speed. Here's an example that demonstrates how to set up and control the motor speed connected to A channel: // Define pins const int ENA = 9; // PWM pin for Motor A const int IN1 = 8; // Direction pin 1 for Motor A const int IN2 = 7; // Direction pin 2 for Motor A void setup() { // Set pin modes pinMode(ENA, OUTPUT); pinMode(IN1, OUTPUT); pinMode(IN2, OUTPUT); } void loop() { // Set motor direction digitalWrite(IN1, HIGH); digitalWrite(IN2, LOW); // Set motor speed using PWM analogWrite(ENA, 127); // 50% Duty cycle, half speed delay(2000); // Run for 2 seconds // Change motor speed analogWrite(ENA, 255); // 100% Duty cycle, full speed delay(2000); // Run for 2 seconds

Hi,I WAs trying to understand the working of the 74HC595 Shift register, so I opened its datasheet.It has two registers(one called shift and the other one storage). But I am confused.. why do you need an extra storage register? What's the purpose of the register? How these two registers are working together to shift the O/P? Attachment :  Block-diagram-of-74HC595-Shift-register.png

Yes Arduino can do floating-point operations, but there’s a few things to keep in mind. 1. On boards like the Uno or Nano (which use the ATmega328P), it supports float and double, but the funny thing is—they’re actually the same thing. Both are 32-bit IEEE 754 floating point numbers. So don’t expect extra precision with double, it's just a float behind the scenes. 2. It can handle basic operations like addition, subtraction, multiplication, and division just fine. But it’s not super fast at it, since the 8-bit microcontrollers don’t have a floating point unit (FPU). That means it does all floating-point math in software, which can slow things down if you’re doing a lot of calculations in your loop. 3. Also, things like sin(), cos(), sqrt() and pow() work, but again, they’re kinda Heavy on processing time. So if you’re working with sensors and need to process stuff quickly, it’s sometimes better to stick with integers where possible, or scale up the values and work in "fixed point" math if you can. 4. One more thing—printing floats with Serial.print() only shows two decimal places by default. You can control that though: float pi = 3.14159; Serial.print(pi); // prints 3.14 Serial.println(pi, 4); // prints 3.1416 So yeah, Arduino can handle floats, but it’s not optimized for Heavy-duty number crunching. If you're doing more advanced math or need higher precision, better to move to something like a Teensy or a 32-bit board like the Arduino Due or even ESP32. But for basic stuff, it’s totally usable.

I think it really depends on the type of projects you're working on. If you're mainly doing simple LED displays, motor control, or basic IoT projects, Arduino boards are perfect. They’re simple and get the job done without much hassle. But if you WAnt to dive into audio processing, real-time data acquisition, or anything that requires Heavy computation, STM32 is a beast. I switched over when I started working on a DIY oscilloscope project because I needed faster ADC and more memory.

@FullBridgeRectifier Thanks for clarifying this. To summarize, there’s a subtle but important distinction here between “how many counts the hardware timer cycles through” (which is indeed 2^n counts) versus “how you usually compute the Duty‑cycle fraction” (which typically uses 2^n − 1 in the denominator so that the maximum register value maps to 100 %). I have edited my answer and added the explanation for this as well.

Good point by @FullBridgeRectifier . Just to clarify for anyone new to this: when we say “divide by 255 instead of 256,” it’s because we’re looking at the maximum value the PWM can take, not the total count of values. This WAy, your Duty cycle calculations always correctly reach 100%.

If you're just starting out with Arduino and electronics, you're definitely not alone—there are some fantastic beginner-friendly resources out there to help you get going without feeling overwhelmed. Helpful YouTube Channels Paul McWhorterOne of the best for beginners. His “Arduino Tutorial Series” is clear, structured, and goes from basics to intermediate projects. Jeremy BlumHis Arduino series is a classic and covers foundational knowledge with well-explained videos. GreatScott!Excellent for understanding how the hardware works behind your projects. Programming Electronics AcademyVery helpful if you're also interested in understanding the coding side deeply. Online Courses Worth Checking Out Udemy – "Arduino Step by Step: More than 50 Hours Complete Course" Taught by Dr. Peter Dalmaris. Very beginner-friendly and includes lifetime access to lessons and materials. Coursera – “Introduction to Programming with Arduino” Offered by University of California, Irvine. Teaches both basic electronics and coding in a structured format.

Both are very different from each other. Here's how: Flash Memory Purpose: Primarily used to store the program (firmware) that runs on the microcontroller. Access Method: Works at the Block level, meaning you write or erase data in chunks, not byte by byte. Endurance: Lower than EEPROM, typically around 10,000 to 100,000 write/erase cycles per Block. Speed: Faster read speeds compared to EEPROM. Capacity: Much larger than EEPROM (e.g., Arduino Uno has 32 KB of Flash memory). EEPROM (Electrically Erasable Programmable Read-Only Memory) Purpose: Designed to store small amounts of data that need to be saved even when the power is off (e.g., device settings or user preferences). Access Method: Data is accessed and written byte by byte, making it perfect for small, frequently changing data. Endurance: It has a high write endurance, typically allowing 100,000 to 1,000,000 write/erase cycles. Speed: Slower compared to Flash. Capacity: Usually much smaller (e.g., Arduino Uno has only 1 KB of EEPROM). What is their purpose in Arduino boards? Flash Memory: This is where your Arduino sketch is stored when you upload it via the IDE. If you need to store constant data like lookup tables, you can use Flash with the PROGMEM directive. EEPROM: You can use it to store user-defined values like calibration data or device settings using the EEPROM library to store it permanently.